CN111654163B - Efficient heat dissipation system for pole coil of hydraulic generator - Google Patents

Abstract

The invention discloses a high-efficiency heat dissipation system for a pole coil of a hydraulic generator, which comprises a stator, a rotor and a cooling heat dissipation system, wherein the rotor comprises a rotating shaft, a magnetic yoke, a bracket for connecting the rotating shaft and the magnetic yoke, a plurality of layers of copper bars arranged on a plurality of iron cores and arranged on the iron cores, a plurality of radial vent holes are respectively arranged on the magnetic yoke, the iron cores and the stator, the two ends of the rotor are air inlet ends, the middle part of the outer side of the stator is an air outlet end, the cooling heat dissipation system is connected with the air inlet ends and the air outlet ends through pipelines, a ventilation turn is arranged between two adjacent layers of copper bars, axial vent holes which extend along the axial direction of the rotor and penetrate through the air inlet ends at the two ends are arranged in the ventilation turn, a plurality of radial heat dissipation holes. The invention can effectively improve the heat dissipation effect of the rotor magnetic pole, reduce the ventilation loss, improve the efficiency of heat dissipation and cooling, and can avoid the complex structure of a heat dissipation system.

Description

Efficient heat dissipation system for pole coil of hydraulic generator

Technical Field

The invention relates to the technical field of hydraulic generators, in particular to a high-efficiency heat dissipation system for a pole coil of a hydraulic generator.

Background

Along with the enhancement of energy-saving and environment-friendly consciousness of people, the hydroelectric power generation as green energy is being vigorously developed, in the field of hydroelectric power generation, a turbine unit is a key part and generally comprises a stator, a rotor rotatably arranged in the stator and a rotating wheel used for driving the rotor to rotate, wherein the rotating wheel is arranged in a volute, the volute is arranged in a machine pit and comprises a plurality of blades, the front surfaces of the blades are upstream surfaces, the back surfaces of the blades are downstream surfaces, one side of the volute is provided with a water inlet pipe with an opening aligned with the upstream surface of the blades, and the other side of the volute is provided with a water outlet pipe. And the rotor comprises a rotor shaft in transmission connection with the rotating wheel, a rotor magnet yoke connected with the rotor shaft through a rotor bracket, and a plurality of magnetic poles uniformly arranged on the outer side of the magnet yoke. The magnetic pole generally includes an iron core, and a copper bar (pole coil) disposed on the iron core. When water flow with high water level difference in the reservoir passes through the water inlet pipe to form high-speed water flow and impacts blades of the rotating wheel to face the water surface, the rotating wheel can rotate and drive the rotor to rotate, and then electric energy is generated.

It is known that when a generator set is in operation, both a stator and a rotor generate certain heat, and if the heat cannot be timely dissipated, the temperature of the generator set is too high, and the insulation performance and the power generation efficiency of the generator set are affected. It is therefore necessary to provide a corresponding heat-sink cooling system in order to maintain the temperature of the stator and rotor within a suitable range.

At present, a large-capacity water turbine generator set is cooled by an air cooling mode generally, so that the insulation problem can be effectively avoided, and the structure is simplified. It can be understood that the temperature rise of the stator and the rotor can be different when the generator set is in different operation conditions. In order to ensure that the temperature is controlled within a proper range, generally, a corresponding rated ventilation amount is set according to the worst operation condition of the unit, and a corresponding ventilation path is set according to the temperature rise state of different heating components under the condition.

The generator set heat dissipation cooling system in the prior art has the following problems: because the magnetic pole part of the rotor is the part with more heat productivity, and the inside of the copper bars which are tightly connected together is difficult to be provided with the cooling air duct, the cooling air is difficult to effectively cool the copper bar part, and the copper bar part is easy to break down due to high temperature when the generator set runs. Generally, one will reduce the temperature of the copper bar section by increasing the ventilation. According to the thermodynamic principle, when the flow speed and the flow of the cooling air reach a certain value, the cooling effect cannot be improved in proportion when the flow speed and the flow are continuously increased, so that the ventilation loss for cooling is increased, and the cooling and heat dissipation efficiency is reduced.

Disclosure of Invention

The invention aims to solve the problems of poor magnetic pole heat dissipation effect and non-uniform temperature of a rotor of the existing hydraulic generator heat dissipation system, and provides a hydraulic generator magnetic pole coil efficient heat dissipation system which can effectively improve the heat dissipation effect of a rotor magnetic pole, remarkably reduce ventilation loss, improve heat dissipation and cooling efficiency, ensure uniform heat dissipation of a generator set and avoid the complex structure of the heat dissipation system.

In order to achieve the purpose, the invention adopts the following technical scheme:

a high-efficiency heat dissipation system for a pole coil of a hydraulic generator comprises a stator, a rotor rotatably arranged in the stator, and a cooling heat dissipation system for cooling and driving cooling air, wherein the rotor comprises a rotating shaft, a magnetic yoke, a bracket for connecting the rotating shaft and the magnetic yoke, and a plurality of magnetic poles arranged on the periphery of the magnetic yoke, the magnetic poles comprise an iron core and a plurality of layers of copper bars arranged on the iron core, a plurality of radial ventilation holes are respectively arranged on the magnetic yoke, the iron core and the stator, the two ends of the rotor are air inlet ends, the middle part of the outer side of the stator is an air outlet end, the input end of the cooling heat dissipation system is connected with the air outlet end of the stator, the output end of the cooling heat dissipation system is connected with the air inlet end of the rotor, a ventilation turn for heat dissipation is arranged between the two adjacent layers of copper bars, an axial ventilation hole which extends along the axial direction of, the areas of the radial radiating holes are gradually increased from the two ends of the rotor to the middle of the rotor.

When the generator set starts to operate and the rotor rotates at a high speed, the cooling system sends cooling air into the rotor through the air inlet end, and meanwhile, the cooling system extracts air at the air outlet end of the stator, so that air pressure is formed between the air inlet end and the air outlet end. The cooling air flows to the air gap between the rotor and the stator through the radial ventilation holes on the rotor yoke and the iron core and then is discharged outwards from the radial ventilation holes of the stator, so that the heat of the rotor and the stator is absorbed. The hot air extracted from the air outlet end is cooled by the cooling heat dissipation system and then sent into the air inlet end of the rotor again, so that circulating cooling heat dissipation is formed.

Compared with the prior art, the invention is provided with the ventilation turns for heat dissipation between two adjacent layers of copper bars, so that the heat on the copper bars can be quickly transferred to the ventilation turns. Because the ventilation circle is internally provided with axial ventilation holes which extend along the axial direction of the rotor and run through the air inlet ends at the two ends, and the outer side of the ventilation circle exposed out of the copper bar is provided with a plurality of radial heat dissipation holes which run through the axial ventilation holes. Like this, when generating set began the operation, under the effect of wind pressure between air inlet end and air-out end, cooling air gets into in the axial ventilation hole from upper and lower both ends, then outwards discharges through radial louvre, outwards discharges through the radial ventilation hole on air gap, the stator at last to can carry out effectual heat dissipation cooling to the circle that ventilates. It can be understood that the two sides of the copper bar are respectively attached to the ventilating turns, so that the copper bar can be effectively cooled and cooled, and the structural complexity and the processing and manufacturing difficulty of the copper bar are not increased. The ventilation turns can be made of aluminum alloy and other materials with good heat-conducting property.

It can be understood that when the cooling air in the axial vent hole of the vent turn flows out from the radial vent hole, the wind pressure at the corresponding position in the axial vent hole is reduced. That is, the wind pressure inside the axial ventilation hole gradually decreases from the air inlet end to the middle position. The area of the radial heat dissipation holes on the ventilation turns is gradually increased from the two ends of the rotor to the middle of the rotor, so that the ventilation quantity of each radial heat dissipation hole can be ensured to be uniform on the premise that the wind pressure is gradually reduced, the heat dissipation cooling effect and the temperature of each position of the rotor in the axial direction are kept uniform, and the heat dissipation cooling efficiency is further improved to the maximum extent. In addition, due to the heat accumulation effect, the temperature of the rotor magnetic pole near the middle part is generally higher than that near the air inlet end. Therefore, the temperature of all parts of the magnetic pole can be ensured to be uniform by reasonably setting the increasing rate of the area of the radial heat dissipation holes on the ventilation turns.

Preferably, the two ends of the rotor are respectively provided with a wind shield, the wind shields are provided with air inlet holes penetrating through the interior of the rotor, and the output end of the cooling and heat-dissipating system is connected with the air inlet holes.

The deep bead at rotor both ends is favorable to making the inside approximate confined space that forms of rotor, and the cool air of the cooling system output of being convenient for gets into inside the rotor, avoids in the higher air admission rotor of external environment temperature to promote the wind pressure between air inlet end and the air-out end, be favorable to promoting the heat dissipation cooling effect.

Preferably, a closed heat absorption hole extending along the axial direction of the rotor is further formed in the ventilation turn, freon R-113 is arranged in the heat absorption hole, the heat absorption hole is inclined outwards from the air inlet end to the middle at one side far away from the center of the rotating shaft, so that a V-shaped flow guide inclined plane protruding outwards from the middle is formed, when the rotor rotates, the freon R-113 in the heat absorption hole generates centrifugal force to be attached to the flow guide inclined plane and flows towards the middle of the rotor along the inclined flow guide inclined plane, the freon R-113 is heated and evaporated in the flowing process to form steam and fills the heat absorption hole, and the freon R-113 steam releases heat at two ends of the heat absorption hole to be liquefied.

In the initial state, the liquid Freon R-113 is accumulated at the lower part of the heat absorption hole, when the generator set runs, the rotating rotor enables the Freon R-113 in the heat absorption hole to generate centrifugal force to be attached to the V-shaped flow guide inclined plane and flow to the middle of the rotor along the inclined flow guide inclined plane, the Freon R-113 absorbs the heat of the ventilation turns in the process of flowing along the flow guide inclined plane to evaporate to form steam and quickly fill the heat absorption hole, and the Freon R-113 steam releases the heat at the position, close to the air inlet, of the heat absorption hole to be liquefied. It can be understood that when the generator set is in operation, the air temperature at the air outlet end is higher than that at the air inlet end, and correspondingly, the temperature of the ventilation turn and the copper bar at the middle position of the rotor is higher than that of the ventilation turn and the copper bar close to the air inlet end. And the boiling point of the Freon R-113 is lower (approximately about 43 ℃), so that the Freon R-113 is evaporated to form steam and quickly fills the heat absorption holes after absorbing heat at the middle positions of the heat absorption holes, the Freon R-113 steam is liquefied to form the Freon R-113 by releasing heat at the air inlet end, and then the Freon R-113 returns to the middle positions of the heat absorption holes along the flow guide inclined plane, and by analogy, the Freon R-113 forms rapid circulating phase change flow in the heat absorption holes, so that the temperatures of the ventilation turns and the copper bars are kept as uniform as possible. The Freon R-113 can absorb or release a large amount of phase change heat during phase change although the temperature is kept unchanged. That is to say, only a small amount of Freon R-113 needs to be filled in the heat absorption holes, so that the temperatures of the ventilation turns and the copper bars can be kept as balanced as possible.

It should be noted that we can ensure the Freon R-113 to evaporate in the middle of the heat absorption hole and condense at the air inlet end by adjusting the concentration of Freon R-113 and the filling amount of Freon R-113 in the heat absorption hole to adapt to different working environments. When the environmental temperature is lower, if the temperature of the ventilation turn at the middle position is lower than the boiling point of Freon R-113, the heat dissipation and cooling effect of the rotor copper bar is sufficient, and the Freon R-113 does not participate in heat conduction at the moment. That is to say, only when the temperature of the ventilation circle is higher than the boiling point of Freon R-113, Freon R-113 can participate in the thermal conduction, and then the heat that makes the ventilation circle is transmitted away fast, and then avoids the local temperature rise of copper bar too high.

Preferably, the ventilation turn is in an annular shape matched with the copper bar, the middle positions of the upper end and the lower end of the ventilation turn are respectively provided with a ventilation bulge, and the axial ventilation hole comprises an annular hole surrounding the ventilation turn and a wind guide hole which is arranged at the ventilation bulge and penetrates through the annular hole.

When the rotor rotates, cooling air at the air inlet end can enter annular holes in two sides of the ventilation turn through air guide holes arranged at the ventilation protrusions, and then flows out of the radial heat dissipation holes of the ventilation turn. It can be understood that the ventilation turn can be made by splicing two flat square pipes, the two ends of each flat square pipe are bent to form the ventilation protrusions, and then the ventilation protrusions of the two flat square pipes are welded together, so that the ventilation turn can be conveniently made.

Preferably, the ventilation turn comprises two annular bottom plates in sealing joint, an inner air guide groove and an outer air guide groove are arranged on one opposite side of each annular bottom plate, when the two annular bottom plates are in sealing joint, the outer air guide grooves on the two annular bottom plates are spliced to form the axial ventilation holes and the radial heat dissipation holes, and the inner air guide grooves on the two annular bottom plates are spliced to form the heat absorption holes.

In this scheme, the circle that ventilates is including controlling two sealed annular bottom plates that join, because relative one side is equipped with interior wind-guiding recess and outer wind-guiding recess on the annular bottom plate, consequently, when two annular bottom plate sealing joints, the concatenation promptly of interior, outer wind-guiding recess on two annular bottom plates constitutes heat absorption hole and axial ventilation hole and radial louvre to the manufacturing of the circle that ventilates is greatly made things convenient for. Particularly, the heat absorption holes and the axial ventilation holes can form a ring shape, so that the heat dissipation and cooling effects of the whole ventilation turn and the copper bar are effectively improved. In addition, the heat absorption holes are positioned on the inner side of the axial ventilation holes, so that the cross interference between the radial heat dissipation holes and the heat absorption holes can be effectively avoided.

Preferably, the ventilation turns are made of aluminum alloy, the axial ventilation holes are formed in the ventilation turns and are far away from the outer side of the axis of the rotor, the heat absorption holes are formed in the ventilation turns and are close to the inner side of the axis of the rotor, and the inner side walls of the heat absorption holes are provided with sintered layers.

The ventilating coil made of aluminum alloy has light weight and fast heat transfer, and the annular bottom plate is formed by precision casting, thus being convenient for processing and manufacturing. The axial ventilation holes arranged on the outer side facilitate the radial heat dissipation holes to directly penetrate through the outer side of the ventilation turn. Particularly, the sintered layer is arranged on the inner side wall of the heat absorption hole, and because the sintered layer has a large number of extremely fine gaps, the capillary action can be formed on the liquid Freon R-113, so that the Freon R-113 in the heat absorption hole can automatically spread to the whole inner side wall of the heat absorption hole, and the heat absorption evaporation of the Freon R-113 is accelerated.

Preferably, the radial ventilation holes arranged on the magnetic yoke, the iron core and the stator are rectangular, the radial ventilation holes correspond to each other in the axial direction, the radial ventilation holes are uniformly distributed in the axial direction, the outer side of the stator is provided with an upper movable adjusting strip and a lower movable adjusting strip corresponding to the radial ventilation holes in the circumferential direction, the two adjusting strips are associated with the power element through a transmission mechanism, the adjusting strips are provided with rectangular adjusting holes corresponding to the radial ventilation holes in number, the distance between every two adjacent adjusting holes is gradually increased from the air inlet end to the middle position of the rotor, the end part of the stator and the radial ventilation holes in the middle position are respectively provided with a temperature sensor,

in an initial state, the adjusting holes in the adjusting strip are partially overlapped with the corresponding radial vent holes in the stator, and the area of the overlapped part of the adjusting holes and the radial vent holes is gradually increased from the air inlet end to the middle position of the rotor; when the generator set runs, a temperature sensor is used for detecting the temperature of air output by the radial ventilation holes at the middle position of the stator and the temperature of air output by the radial ventilation holes at the end parts, so that a temperature difference T is obtained, the temperature difference T is compared with a set temperature difference delta T, when the temperature T is less than or equal to 0.95 delta T, the power element enables the two adjusting strips to be relatively close to each other through the transmission mechanism, the area of the overlapping part of the adjusting holes and the radial ventilation holes is increased, when the temperature T is more than or equal to 1.05 delta T, the power element enables the two adjusting strips to be separated from each other through the transmission mechanism, the area of the overlapping part of the adjusting holes and the radial ventilation holes is decreased, and when the temperature T is less than 0.95 delta T and less than 1.05 delta T, the positions of the adjusting strips are kept unchanged.

The invention is provided with an upper and a lower movable adjusting strips outside the stator, and the adjusting strips are provided with rectangular adjusting holes corresponding to the number of the radial vent holes. Therefore, the adjusting strip covers the outer side of the stator, and the overlapped part of the adjusting holes in the adjusting strip and the corresponding radial vent holes in the positioning form the size of the final radial vent hole outlet of the stator.

In the initial state, the adjusting holes in the adjusting strip are overlapped with the corresponding radial ventilation holes in the stator to form smaller radial ventilation hole outlets, and the distance between every two adjacent adjusting holes is gradually increased from the air inlet end to the middle position of the rotor. Therefore, the area of the overlapped part of the adjusting hole and the radial vent hole is gradually increased from the air inlet end to the middle position of the rotor, namely, the area of the outlet of the radial vent hole is gradually increased from the air inlet end to the middle position of the rotor. When the Δ T is less than or equal to 0.95 Δ T, the temperature difference is minimal, and the ventilation quantity of the radial ventilation holes close to the middle of the rotor is overlarge, so that the power element can be controlled by the controller to act, the upper movable adjusting strip and the lower movable adjusting strip move relatively and close to each other, and the outlet areas of the radial ventilation holes are synchronously increased to the same area. It can be understood that the percentage increase of the outlet area of the radial vent hole near the air inlet end is greater than the percentage increase of the outlet area of the radial vent hole near the middle position of the rotor, so that more cooling air entering the rotor from the air inlet hole enters the radial vent hole near the air inlet end, and the flow rate of the cooling air in each radial vent hole meets the cooling requirement of the heat dissipation system. Similarly, when Δ T is larger than or equal to 1.05 δ T, the temperature difference is too large, and the ventilation volume of the radial ventilation holes close to the air inlet end is too large, so that the power element can be controlled by the controller to act, the upper movable adjusting strip and the lower movable adjusting strip can synchronously move and are separated from each other, the area of the outlet of each radial ventilation hole is synchronously reduced by the same area, the reduction percentage of the area of the outlet of each radial ventilation hole close to the air inlet end is larger than that of the outlet of each radial ventilation hole close to the middle position of the rotor, and more cooling air entering the rotor from the air inlet hole enters the radial ventilation holes close to the middle position of the rotor, so that the flow of the cooling air in each radial ventilation hole meets the cooling requirement of the heat dissipation system. When 0.95 delta T < 1.05 delta T, it is indicated that the cooling air flow of the radial vents is suitable, so that the position of the adjusting strip can be maintained.

Therefore, the invention has the following beneficial effects: the heat dissipation effect of the rotor magnetic pole can be effectively improved, the ventilation loss is remarkably reduced, the heat dissipation and cooling efficiency is improved, the uniform heat dissipation of the generator set is ensured, and the complex structure of a heat dissipation system can be avoided.

Drawings

Fig. 1 is a schematic view of a structure of a rotor and a stator of the present invention.

Fig. 2 is a schematic view of a structure of the end face of the rotor.

Fig. 3 is a schematic view of a structure of a magnetic pole portion of a rotor.

Fig. 4 is a schematic side view of a ventilation turn.

Fig. 5 is a cross-sectional view of the vent turn at the heat absorption aperture.

Fig. 6 is a schematic view of a structure of a ventilation turn.

Fig. 7 is a schematic view of a structure of the annular base plate.

Fig. 8 is a schematic view of a structure of the stator outer side adjusting strip.

In the figure: 1. the air guide structure comprises a stator 2, a rotor 21, an air inlet end 22, an air outlet end 23, a rotating shaft 24, a magnetic yoke 241, a radial vent hole 25, a support 26, an iron core 27, a copper bar 3, a regulating strip 31, a regulating hole 5, a ventilation turn 51, an axial vent hole 511, an annular hole 512, an air guide hole 52, a radial heat dissipation hole 53, a heat absorption hole 54, a flow guide inclined plane 55, a ventilation bulge 56, an annular bottom plate 561, an inner air guide groove 562 and an outer air guide groove.

Detailed Description

The invention is further described with reference to the following detailed description and accompanying drawings.

As shown in fig. 1, a high-efficiency heat dissipation system for pole coils of a hydro-generator comprises a stator 1, a rotor 2 rotatably arranged in the stator, and a cooling heat dissipation system (not shown in the figure) for cooling and driving cooling air, wherein as shown in fig. 2, the rotor comprises a middle rotating shaft 23, a peripheral magnetic yoke 24, a bracket 25 for connecting the rotating shaft and the magnetic yoke, and a plurality of magnetic poles arranged on the periphery of the magnetic yoke, and each magnetic pole comprises an iron core 26 and a plurality of layers of rectangular frame-shaped copper bars 27 arranged on the iron core. In order to facilitate heat dissipation and cooling of the rotor and the stator, as shown in fig. 3, a plurality of radial ventilation holes 241 are required to be respectively disposed on the yoke, the core, and the stator at intervals along the axial direction. In addition, in this embodiment, the axes of the rotor and the stator are vertically arranged, the upper end and the lower end of the rotor are the air inlet end 21 for inputting cooling air, and the outer side of the stator is the air outlet end 22 for outputting cooling air, preferably, the air outlet end is located at the middle position of the stator in the axial direction, the input end of the cooling and heat dissipating system is connected with the air outlet end of the stator through a pipeline, and the output end of the cooling and heat dissipating system is connected with the air inlet end of the rotor through a pipeline. Of course, the cooling heat dissipation system should include a gas cooling device for cooling the gas flow in the pipeline,

in addition, as shown in fig. 3 and 4, a ventilation turn 5 for heat dissipation needs to be arranged between two adjacent layers of copper bars, and the shape of the ventilation turn is a rectangular frame matched with the shape of the copper bars, that is, the ventilation turn at least has two long sides extending along the axial direction of the rotor and two transverse short sides. At least, two long sides of the ventilation circle are internally provided with axial ventilation holes 51 which extend along the axial direction of the rotor and penetrate through air inlet ends at the upper end and the lower end, a plurality of radial heat dissipation holes 52 which penetrate through the axial ventilation holes are arranged at the outer side of the ventilation circle exposed out of the copper bar, and the areas of the radial heat dissipation holes are gradually increased from the two ends of the rotor to the middle of the rotor.

It should be noted that, because the ventilation turn is clamped between the adjacent copper bars, the ventilation turn has four upper, lower, left and right outer side surfaces exposed out of the copper bars. When the two long sides of the ventilation turn are internally provided with the ventilation holes, the radial heat dissipation holes can be formed in the left outer side face and the right outer side face. In addition, the radial heat dissipation holes are rectangular holes, the vertical direction is the length direction, and the horizontal direction is the width direction. The widths of all the radial radiating holes are the same, and the lengths of the radial radiating holes are gradually lengthened from the two ends of the rotor to the middle of the rotor, so that the areas of the radial radiating holes are gradually increased.

When the generator set starts to operate and the rotor rotates at a high speed, the cooling heat dissipation system is started to send out cooling air, the cooling air is sent into the rotor through the air inlet end, meanwhile, the cooling heat dissipation system extracts air at the air outlet end of the stator, so that the cooling air forms continuous flow in the rotor and the stator, and air pressure is formed between the air inlet end and the air outlet end. The cooling air flows to the air gap between the rotor and the stator through the radial ventilation holes on the rotor yoke and the iron core and then is discharged outwards from the radial ventilation holes of the stator, so that the heat of the rotor and the stator is absorbed to be hot air. The hot air extracted from the air outlet end is cooled by the cooling heat dissipation system and then sent into the air inlet end of the rotor again to form circulating cooling heat dissipation.

Meanwhile, under the action of wind pressure between the air inlet end and the air outlet end, cooling air enters the axial ventilation holes of the ventilation turns from the upper end and the lower end, is discharged outwards through the radial heat dissipation holes, and is discharged outwards through the air gaps and the radial ventilation holes in the stator, so that the ventilation turns can be cooled effectively in a heat dissipation mode. Because the two sides of the copper bar are respectively attached to the ventilation turns, the copper bar can be effectively cooled, and the structural complexity and the processing and manufacturing difficulty of the copper bar are not increased. Of course, the ventilation turns can be made of aluminum alloy and other materials with good heat-conducting property.

It can be understood that when the rotor rotates at a high speed, the cooling air in the axial ventilation holes of the ventilation turns can be thrown out from the radial ventilation holes at a high speed under the action of centrifugal force, and similarly, the cooling air in the radial ventilation holes of the magnet yoke and the iron core can quickly enter the air gap between the rotor and the stator after being acted by the centrifugal force and then is discharged outwards from the radial ventilation holes of the stator. That is to say, the rotation of rotor forms a drive effect to cooling air to be favorable to cooling air's accelerated flow, and then promote the heat dissipation cooling effect.

It should be noted that, when the cooling air in the axial ventilation hole of the ventilation turn flows out from the radial heat dissipation hole, the air pressure at the corresponding position in the axial ventilation hole is reduced. That is, the wind pressure inside the axial ventilation hole gradually decreases from the air inlet end to the middle position. The area of the radial heat dissipation holes on the ventilation turns is gradually increased from the two ends of the rotor to the middle of the rotor, so that the ventilation quantity of each radial heat dissipation hole can be ensured to be uniform on the premise that the wind pressure is gradually reduced, the heat dissipation cooling effect and the temperature of each position of the rotor in the axial direction are kept uniform, and the heat dissipation cooling efficiency is further improved to the maximum extent.

In order to improve the wind pressure in the rotor, wind shields can be arranged at the upper end and the lower end of the rotor respectively and are fixedly connected with the stator, and therefore the wind shields are prevented from rotating along with the rotor. Set up the fresh air inlet that link up the rotor inside on the deep bead, cooling system's output is connected with the fresh air inlet through the pipeline, thereby make rotor and stator inside form roughly confined circulation flow space through pipeline and cooling system, the cold air of the cooling system output of being convenient for gets into inside the rotor, avoid in the higher air admission rotor of temperature among the external environment, and promote the wind pressure between air inlet end and the air-out end, in order to accelerate cooling air's velocity of flow, promote the heat dissipation cooling effect.

It can be understood that when the generator set is in operation, the air temperature at the air outlet end is higher than that at the air inlet end, and correspondingly, the temperature of the ventilation turn and the copper bar at the middle position of the rotor is higher than that of the ventilation turn and the copper bar close to the air inlet end.

As a preferable scheme, as shown in figure 5, a closed heat absorption hole 53 extending along the axial direction of the rotor can be arranged inside the ventilation turn, Freon R-113 is filled in the heat absorption hole, one side of the heat absorption hole, which is far away from the center of the rotating shaft, inclines from the air inlet end to the middle to the outer side, so that a V-shaped flow guide inclined surface 54 protruding to the outer side in the middle is formed, and the included angle of the V-shaped flow guide inclined surface can be 177-178.5 degrees.

In the initial state, liquid Freon R-113 is accumulated at the lower part of the heat absorption hole, when the generator set runs and the rotor rotates, the liquid Freon R-113 in the heat absorption hole generates centrifugal force to be attached to the guide inclined plane at the outer side and flows to the middle of the rotor along the inclined guide inclined plane, the Freon R-113 is heated and evaporated in the flowing process to form steam and fill the heat absorption hole, the Freon R-113 steam releases heat at two ends of the heat absorption hole to be liquefied, and then flows back to the middle position of the heat absorption hole along the guide inclined plane, and by analogy, the Freon R-113 forms rapid circulating phase change flowing in the heat absorption hole, so that the temperatures of the ventilation turns and the copper bars are kept as uniform as possible.

It should be noted that, when the environmental temperature is low, if the temperature of the ventilation turn at the middle position is lower than the boiling point of freon R-113, the heat dissipation and cooling effect of the rotor copper bar is sufficient, and the freon R-113 does not generate phase change at this time, i.e., does not participate in heat conduction. That is to say, only when the temperature of ventilation circle intermediate position is higher than freon R-113's boiling point, freon R-113 just can participate in thermal conduction, and then makes the heat of ventilation circle transmit away fast, and then avoids the local temperature rise of copper bar too high.

Furthermore, as shown in fig. 6, ventilation protrusions 55 may be respectively disposed at the middle positions of the upper and lower short sides of the ventilation turn, the axial ventilation hole includes an annular hole 511 surrounding the ventilation turn and an air guide hole 512 disposed at the ventilation protrusion, the inner end of the air guide hole penetrates through the annular hole, and the outer end of the air guide hole penetrates through the ventilation protrusions.

Like this, when the rotor rotated, the cooling air accessible of air inlet end set up in the annular hole in the circle that ventilates is got into in the wind-guiding hole of ventilating protruding department, outwards flows from the radial louvre of ventilating the circle then. It should be noted that the ventilation turn can be made by splicing two flat square tubes, the two ends of the flat square tube are bent to form the ventilation protrusions, and then the two ventilation protrusions of the flat square tube bent to be in a shape like a Chinese character 'ji' are welded together, so that the ventilation turn can be conveniently made. In addition, the upper short side and the lower short side of the ventilation turn can be integrally protruded outwards to form a ventilation protrusion, and a plurality of air guide holes are arranged on the ventilation protrusion at intervals, so that more cooling air can enter the axial ventilation holes.

Further, as shown in fig. 7, the ventilation turn may also include two rectangular ring-shaped bottom plates 56, which are attached to each other and are in sealing engagement with each other, and an inner wind guiding groove 561 and an outer wind guiding groove 562 are disposed on opposite sides of the bottom plates. When two annular bottom plates are in sealing joint, the outer air guide grooves on the two annular bottom plates are spliced to form the axial ventilation holes and the radial heat dissipation holes, the inner air guide grooves on the two annular bottom plates are spliced to form the closed heat absorption holes, so that the ventilation turns are greatly convenient to process and manufacture, the heat absorption holes and the axial ventilation holes at the moment can form a ring shape, the heat dissipation cooling effect of the whole ventilation turns and the copper bars is effectively improved, and the cross interference between the radial heat dissipation holes and the heat absorption holes is avoided. Preferably, the annular base plate may be formed by a die-casting process using an aluminum alloy, and the two annular base plates may be integrally coupled by fastening screws.

In addition, a sintered layer can be arranged on the inner side wall of the heat absorption hole, so that a large number of extremely fine gaps with capillary action are formed on the inner side wall of the heat absorption hole. The liquid Freon R-113 in the heat absorption hole can automatically spread to the inner side wall of the whole heat absorption hole under the capillary action of the sintering layer, so that the Freon R-113 can be accelerated to fully absorb the heat of the ventilation turns to be quickly evaporated.

As another preferable scheme, the radial ventilation holes of the yoke, the core and the stator are arranged in a rectangular shape, and the positions of the radial ventilation holes of the yoke, the core and the stator in the axial direction correspond to each other, and the radial ventilation holes are uniformly distributed in the axial direction, so that the cooling air can be smoothly discharged outwards through the radial ventilation holes. That is to say, set up the radial ventilation hole of a plurality of rows on yoke, iron core and the stator, every radial ventilation hole of row evenly distributed in the axial to each radial ventilation hole of row evenly distributed in the circumference.

In addition, as shown in fig. 8, two adjusting strips 3 which can move up and down are arranged on the outer side of the stator corresponding to each row of radial ventilation holes in the circumferential direction, the two adjusting strips are associated with a power element through a transmission mechanism, rectangular adjusting holes 31 corresponding to the number of the radial ventilation holes are arranged on the adjusting strips, the distance between every two adjacent adjusting holes on the adjusting strips is gradually increased from the air inlet end to the middle position of the rotor, and temperature sensors are respectively arranged at the end part of the stator and the radial ventilation holes at the middle position. Preferably, the lateral width of the adjusting hole is the same as the width of the corresponding radial ventilation hole on the stator, and the length of the adjusting hole in the up-down direction is greater than the length of the corresponding radial ventilation hole on the stator.

In an initial state, each adjusting hole on the adjusting strip is overlapped with the upper part of the corresponding radial vent hole on the stator, and the overlapped part is the outlet of the radial vent hole on the stator. That is, the lower portions of the corresponding radial vent holes on the stator are covered by the adjustment strip. In addition, because from the air inlet end to the intermediate position of rotor, the interval between two adjacent regulation holes on the regulation blade strip increases gradually, consequently, from the intermediate position of air inlet end to rotor, the area of regulation hole and radial ventilation hole overlap portion increases gradually. That is, the portion of the lower portion of the radial vent hole covered by the adjustment strip is gradually reduced.

When the generator set runs, the temperature sensor is used for detecting the temperature of the air output by the radial ventilation holes in the middle of the stator and the temperature of the air output by the radial ventilation holes at the ends, so that a temperature difference Δ T is obtained, and the temperature difference Δ T is compared with a preset temperature difference Δ T;

when the Δ T is less than or equal to 0.95 Δ T, the temperature difference is small, the ventilation quantity of the radial ventilation holes close to the middle of the rotor is overlarge, and the power element can be controlled by the controller to act, so that the upper movable adjusting strip and the lower movable adjusting strip move relatively and close to each other, and the outlet area of each radial ventilation hole is synchronously increased by the same area. It can be understood that the percentage increase of the outlet area of the radial vent hole near the air inlet end is greater than the percentage increase of the outlet area of the radial vent hole near the middle position of the rotor, so that more cooling air entering the rotor from the air inlet hole enters the radial vent hole near the air inlet end, and the flow rate of the cooling air in each radial vent hole meets the cooling requirement of the heat dissipation system.

When the temperature T is more than or equal to 1.05 delta T, the temperature difference is overlarge, the ventilation quantity of the radial ventilation holes close to the air inlet end is overlarge, therefore, a controller can control the power element to act, so that the upper movable adjusting strip and the lower movable adjusting strip move synchronously and are separated from each other, the area of the outlet of each radial ventilation hole is reduced synchronously by the same area, the area reduction percentage of the outlet of each radial ventilation hole close to the air inlet end is larger than that of the outlet of each radial ventilation hole close to the middle position of the rotor, and more cooling air entering the rotor from the air inlet hole enters the radial ventilation holes close to the middle position of the rotor, so that the flow of the cooling air in each radial ventilation hole meets the cooling requirement of a heat dissipation system.

When 0.95 delta T < 1.05 delta T, it is indicated that the cooling air flow of the radial vents is suitable, so that the position of the adjusting strip can be maintained.

It should be noted that the power element may be a stepping motor, and the transmission mechanism may include a driving screw rod in transmission connection with a shaft of the stepping motor through a gear, two ends of the driving screw rod are external threads with opposite rotation directions, two ends of the driving screw rod are in threaded connection with a driving nut, and the driving nut is fixedly connected with the adjusting strip on the corresponding side. When the stepping motor drives the driving screw rod to rotate, the upper driving nut and the lower driving nut can be driven to mutually approach or be coincidently separated in the circumferential direction.

Claims (6)

1. A high-efficiency heat dissipation system for a pole coil of a hydraulic generator comprises a stator, a rotor rotatably arranged in the stator and a cooling heat dissipation system for cooling and driving cooling air, wherein the rotor comprises a rotating shaft, a magnetic yoke, a bracket for connecting the rotating shaft and the magnetic yoke and a plurality of magnetic poles arranged on the periphery of the magnetic yoke, the magnetic poles comprise an iron core and a plurality of layers of copper bars arranged on the iron core, and a plurality of radial vent holes are respectively arranged on the magnetic yoke, the iron core and the stator, and the high-efficiency heat dissipation system is characterized in that the two ends of the rotor are air inlet ends, the middle part of the outer side of the stator is an air outlet end, the input end of the cooling heat dissipation system is connected with the air outlet end of the stator, the output end of the cooling heat dissipation system is connected with the air inlet end of the rotor, a ventilation turn for heat dissipation is arranged between the two adjacent layers of copper bars, from the both ends of rotor to the rotor in the middle of, the area of radial louvre increases gradually, still is equipped with the confined hole of inhaling heat along rotor axial extension inside the circle of ventilating, and the downthehole freon R-113 that is equipped with of heat absorption, the hole of inhaling heat is kept away from pivot center one side and is leaned on to the outside from the air inlet end to the centre to form the bellied V-arrangement water conservancy diversion inclined plane in middle to the outside, be equipped with the sintering layer on the inside wall in heat absorption hole, when the rotor rotates, the downthehole freon R-113 of heat absorption produces centrifugal force and pastes and lean on the water conservancy diversion inclined plane, and flow to the rotor centre along the water conservancy diversion inclined plane of slope, freon R-113 is heated the evaporation in-process and is formed steam and is full of the hole of inhaling heat, freon R-113 steam.

2. The pole coil efficient heat dissipation system of a hydraulic generator as recited in claim 1, wherein wind shields are provided at both ends of the rotor, respectively, the wind shields are provided with air inlet holes penetrating the interior of the rotor, and the output end of the cooling heat dissipation system is connected to the air inlet holes.

3. The efficient heat dissipation system for the pole coil of the hydraulic generator according to claim 1, wherein the ventilation turn is in an annular shape matched with the copper bar, the middle positions of the upper end and the lower end of the ventilation turn are respectively provided with a ventilation bulge, and the axial ventilation hole comprises an annular hole surrounding the ventilation turn and a wind guide hole arranged at the ventilation bulge and penetrating through the annular hole.

4. The pole coil efficient heat dissipation system of a hydraulic generator as recited in claim 1, wherein the ventilation coil comprises two annular bottom plates which are hermetically joined, and an inner wind guiding groove and an outer wind guiding groove are formed on opposite sides of the annular bottom plates, when the two annular bottom plates are hermetically joined, the outer wind guiding grooves on the two annular bottom plates are spliced to form the axial ventilation holes and the radial heat dissipation holes, and the inner wind guiding grooves on the two annular bottom plates are spliced to form the heat absorption holes.

5. The efficient heat dissipation system for the pole coil of the hydraulic generator as recited in claim 1, wherein the ventilation turn is made of aluminum alloy, the axial ventilation holes are disposed on an outer side of the ventilation turn away from the axis of the rotor, and the heat absorption holes are disposed on an inner side of the ventilation turn close to the axis of the rotor.

6. The pole coil efficient heat dissipation system of a water turbine generator as recited in claim 1, wherein the radial ventilation holes formed in the yoke, the core and the stator are rectangular and correspond to each other in axial direction, each radial ventilation hole is uniformly distributed in axial direction, two upper and lower movable adjustment strips are provided on the outer side of the stator corresponding to the radial ventilation holes in circumferential direction, the two adjustment strips are associated with the power element through a transmission mechanism, the adjustment strips are provided with rectangular adjustment holes corresponding to the number of the radial ventilation holes, the interval between two adjacent adjustment holes is gradually increased from the air inlet end to the middle position of the rotor, temperature sensors are provided at the end portion of the stator and the radial ventilation holes at the middle position respectively,

in an initial state, the adjusting holes in the adjusting strip are partially overlapped with the corresponding radial vent holes in the stator, and the area of the overlapped part of the adjusting holes and the radial vent holes is gradually increased from the air inlet end to the middle position of the rotor; when the generator set runs, a temperature sensor is used for detecting the temperature of air output by the radial ventilation holes at the middle position of the stator and the temperature of air output by the radial ventilation holes at the end parts, so that a temperature difference T is obtained, the temperature difference T is compared with a set temperature difference delta T, when the temperature T is less than or equal to 0.95 delta T, the power element enables the two adjusting strips to be relatively close to each other through the transmission mechanism, the area of the overlapping part of the adjusting holes and the radial ventilation holes is increased, when the temperature T is more than or equal to 1.05 delta T, the power element enables the two adjusting strips to be separated from each other through the transmission mechanism, the area of the overlapping part of the adjusting holes and the radial ventilation holes is decreased, and when the temperature T is less than 0.95 delta T and less than 1.05 delta T, the positions of the adjusting strips are kept unchanged.

Images